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Kakapo -

The exotic kakapo, a nocturnal, ground-dwelling member of the parrot family endemic to New Zealand, is critically endangered and one of the rarest flightless birds in the world.

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South Island takahē -

Indigenous to New Zealand, the South Island takahē is the largest living member of the rail family, and is an endangered species.

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Weka -

Another flightless bird native to New Zealand, the vulnerable weka is more often heard than seen.

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Common ostrich -

The common ostrich is the largest, tallest, and heaviest living flightless bird in the world. These mighty birds, found across vast swathes of Africa, can grow up to 2.74 m (9 ft) tall and can weigh more than 136 kg (300 lbs).

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Somali ostrich -

The more vulnerable Somali ostrich is native to the Horn of Africa, and is also known as the blue-necked ostrich.

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Greater rhea -

Native to Argentina, Bolivia, Brazil, Paraguay, and Uruguay, the near threatened greater rhea is the largest bird in South America.

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Darwin's rhea -

Darwin's rhea, also known as the lesser rhea, stands an impressive 90 to 100 cm (35–39 in) tall. It's found in the Altiplano and Patagonia in South America.

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Fuegian steamer duck -

There are four species of steamer duck, three of which are flightless. The Fuegian, or Magellanic flightless steamer duck, is the largest of the species and inhabits the rocky coasts and coastal islands from southern Chile to Tierra del Fuego.

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Falkland steamer duck -

One of only two bird species endemic to the Falkland Islands, the other being Cobb's wren, this rare but well-protected bird is known locally as the logger duck.

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Chubut steamer duck -

More vulnerable is the Chubut steamer duck, which was only recognized as a separate species in 1981. It's endemic to southern Argentina.

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Flightless cormorant -

Endemic to the Galapagos Islands and therefore often referred to as the Galapagos cormorant, this is the only known cormorant that has lost the ability to fly. Its conservation status is listed as vulnerable.

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Southern cassowary -

The three species of cassowary are all native to New Guinea and Australia, and all flightless. The southern cassowary is the second heaviest bird in the world (behind only the ostrich).

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Northern cassowary -

Large and stocky, the northern cassowary is also known as the golden-necked cassowary for its amber-hued neck.

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Dwarf cassowary -

The dwarf cassowary is also called Bennett's cassowary after English-born Australian naturalist George Bennett (1804–1893), who was the first scientist to examine cassowaries in detail.

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Emu -

The second-largest living bird by height after the ostrich, the emu is an important cultural icon of Australia. The Tasmanian, Kangaroo Island, and King Island subspecies of this bird became extinct in the late 1800s.

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Junin grebe -

Found only on Lake Junin in west-central Peru, the endangered Junin grebe relies solely on its exceptional diving skills to sustain itself.

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Titicaca grebe -

Like the Junin grebe, the Titicaca grebe is named for the lake where its main population is found. However, this species' range extends to the Altiplano of Peru and Bolivia, and is equally endangered.

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Kiwi -

The kiwi is endemic to New Zealand, and is a cherished icon of the nation. All species of kiwi are flightless. And did you know this? In proportion to its body size, the female kiwi lays a bigger egg than almost any other bird. In fact, kiwi eggs are six times as big as normal for a bird of its size.

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North Island brown kiwi -

With 35,000 remaining, the North Island brown kiwi is the most common kiwi, but is still listed as vulnerable on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species.

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Little spotted kiwi -

The near threatened little spotted kiwi, meanwhile, is found only on a number of small offshore islands and mainland reserves.

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Penguin -

All 18 species of penguins are flightless, of which 11 are Globally Threatened, according to the IUCN Red List. They live almost exclusively in the Southern Hemisphere with only one species, the Galapagos penguin, found north of the Equator. Pictured is the chinstrap penguin.

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Yellow-eyed penguin -

The yellow-eyed penguin, affectionately  nicknamed the hoiho, is the rarest penguin in the world, with only 225 pairs left on New Zealand's mainland. In 2019, the hoiho won New Zealand's coveted Bird of the Year competition to become the first penguin to achieve the honor in its 14-year history.

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Emperor penguin -

The handsome emperor penguin is the tallest and heaviest of all living penguin species and is endemic to Antarctica.

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Little penguin -

At the other end of the scale, the diminutive little penguin grows to an average of 33 cm (13 in) in height and 43 cm (17 in) in length. The birds are found on the coastlines of southern Australia and New Zealand.

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Okinawa rail -

The existence of the Okinawa rail was only confirmed in 1978, on Japan's Okinawa Island. It's an endangered, almost flightless member of the rail family, and in fact is rarely seen in the air.

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Auckland teal -

So small are the Auckland teal's wings that the species has lost the power of flight. The vulnerable bird is endemic to the Auckland Islands south of New Zealand.

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Campbell teal -

Related to the Auckland teal, the Campbell teal is also permanently grounded due to insufficient wing power. The species, named for the Campbell Island group of New Zealand, is also listed as vulnerable. 

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Lord Howe woodhen -

Endemic to Lord Howe Island off the Australian coast, this small dainty member of the rail family numbered less than 30 birds in the 1970s. While the adult population now numbers in excess of 200, the Lord Howe woodhen remains an endangered species.

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Tasmanian native hen -

One of 12 species of birds endemic to the Australian island of Tasmania, the appropriately-named Tasmanian native hen thrives on the fertile pastureland carpeting the island. The bird is nifty on its feet, and can reach speeds of up to 48 kph (30 mph) during a full dash.

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Giant coot -

Oddly, immature giant coots are quite nimble in the air. It's only after they reach adulthood and gain weight that the birds are considered functionally flightless. The lakes of Peru, Bolivia, Chile, and Argentina are where you can admire them.

Sources: (Falklands Conservation) (Peru Travel) (Kiwis for Kiwi) (IUCN Red List) (BBC) (Beauty of Birds)

See also: Earth's best destinations to see wildlife

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